I'm sure players dont sit at home reading message boards thinking they should or shouldn't join a club.
You'd be surprised that players do actually read forums prior to joining a club to gather an idea about what the fans' general mentality towards the running of the Club, current players and new signings is.
I remember not so long ago, reading on a club forum on here that mentioned a potential player felt disheartened by what he'd read on the forum and as a result turned the club down because of the way the fans reacted about his possible signing once it had leaked out.
They may be few and far between but it does happen. I would imagine Agents' publicity is worse than reading forums, but going on past experiences it's not really something I think our club wish to have happen again.